Propeller.



E. S. JACOBS.

PROPELLER. APPLICATION PILEDBI IPT. 2, 1902.

10 10mm. 2 sums-sum 1.

No. 728,925. PATENTED MAY 26, 1903.

M W f PATENTED MAY 26, 1903. E. S. JACOBS.

PROPELLERf APPLIOATION rILnn SEPT. 2, 1902.

2 SHEETS-SHEET 2.

N0 MODEL.

No. 728,925. g

UNTTnn STATES Patented May 26, 1903.

PATENT OFFICE.

PROPELLER.

SPECIFICATION forming part of Letters Patent No. 728,925, dated May 26, 1903.

Application filed September 2,1902. Serial No. 121,852. (No model.)

To all 11/77/0772, it may concern:

Be it known that I, EILT S. JACOBS, residing at Neuharlingersiel, Germany, have invented certain new and useful Improvements in Propellers, of which the following is a specification.

The present invention relates to propellers for ships, especially to auxiliary propellers for sailing-ships, the blades of which are pivotally mounted upon an axis perpendicular to the shaft in such a manner that when the engineis stopped, but the ship is yet moving, the blades automatically come into the longitudinal perpendicular plane of the ship. To this end the blades of the propeller are of unsymmetrical shape with respect to their axis in such a way that the greater part of their surface lies behind the axis of their rotation.

The essential feature of thisinvention is the arrangement of a device capable of being actuated from any suitable point on the ship, the said device serving to arrest the blades of the propeller in any one of three distinct positions, one of these being in line with the longitudinal perpendicular plane of the ship, the other two lying in a suitable angle thereto. One of these two latter positions results when the propeller is turning to the right and the other when it is turning to the left. If the blades of the propeller are not arrested by the fixing apparatus, they will automatically take their position in the longitudinal perpendicular plane of the ship as soon as the shaft'is stopped While the ship is yet in motion, because the center of gravity of the surface of the blades lies behind the axis, around which they can pivot upon the boss of the propeller, as above explained. If, on the contrary, the machine is started and the propeller-shaft begins to turn, the blades of the propeller, in consequence of theirunsymmetrical form, will rock about their axis of rotation-that is to say, to the right or the left, the direction of rocking movement depending upon the shaft being rotated to the right or the left. The position now assumed by the blades will be marked by pins fixed to suitable pieces supporting the blades of the propeller and' rocking with them upon the boss, the said pins bearing against other pins provided upon the boss on the right and left side of the plane passing through the axis of the blades matically rock through certain angles to the right and left in the above-described manner are already known; but, as is quite evident, a backward movement is wholly impossible, as those propellers can only produce a forward driving of a ship. Of course to be able to use such a propeller provided with blades rocking automatically to the right or left, also for driving the ship backward, the arrangement for arresting the blades representing this invention has been provided, for it is evident that if the blades have been turned to either side and retained in this position a backward movement of the ship is possible as soon as the direction of rotation .of the main shaft is changed. If, on the otherhand, the propeller-blades, with the engine stopped and the ship yet moving in a forward direction, have assumed their position in the longitudinal perpendicular plane of the ship and are retained there by means of the present device, they are advantageous for representing an increase of the longitudinal perpendicular plane of the ship, this fact being of importance in sailing-ships for decreasing the leeway.

The accompanying drawings represent the invention.

Figure 1 is an elevation of a ship provided with a'propeller according to this invention. Fig. 2 is a section through the boss of the propeller. Fig. 3 shows the arrangement of the propeller between the rudder and the stern with a section through the boss.

The ship a, Fig. 1, which at the stern is provided with a propeller 19, carries a pulling mechanism 0, capable of being actuated from the captains bridge and provided with a cord or chain e, passing over rollers d, the said pulling mechanism 0 being used for retaining the propeller-blades in a certain position or to release the same. The blades f of the propeller are connected with one another and with an axle h by the aid of suitable blocks g, the said axle h permitting the blades to be rotatably mounted and secured on the boss 7t. Nuts 2' are provided on both ends of the axle h in order to prevent any displacement of the axle in a longitudinal direction. At its outer end the boss forms, with the help of pins q, a guide for a plate 10, which is provided on one side with pins 0 and on the other with a pin 5. The latter is screwed into a piece 25, guided between slide-pieces u, secured to tho rudder-frame, and will therefore be moved upon the movement of the piece t. Each of the pins 0 on the other side of the platep corresponds with three openingsn in each of the blocks 9 of the propeller, the said openings being so arranged that the pins 0 can enter within the blocks 9 when the propeller-blades have assumed their central position as well as when they are in their rocked. positions to right or left.

By means of these pins the blades of the propeller are fixed to the boss and are prevented from turning about their axle h. The guide-piece t is connected with the above mentioned pulling mechanism 0 by a cord or chain 6. The pins q carry springs r, tending to always press the plate p against the boss.

The operation of the described arresting device is as follows:. Assuming the propellerblades are in one of their positions suitable for driving the ship into which they are first brought by pulling the device 0 and allowing of their rocking to the right or left with their axis, and in which positions they are then retained by pins V and W and by releasing the apparatus 0, thereby enabling the pins 0 to enter into the corresponding openings of the pieces g, uponthe revolution of the engine in one direction the propeller will then drive the ship forward, while the revolution of the engine in an opposite direction drives the ship back. If, now, the engine is stopped and the pins 0 of the plate 19 are withdrawn from the openings n of the pieces 9, by pulling the cord e against the action of the springs r the blades of the propeller are released and-will come into their central position in consequence of the water-pressure while the ship is continuing its forward movement. Then by releasing the cord 6 the bolts 0 will again be permitted to enter within other openings of the pieces 9 under the influence of the springs r and are again brought into engagement with the propeller, so that the blades are secured in their central position. If now the propeller is again to be used for driving the ship, the securing apparatus of the blades is. again loosened and the engine is put into motion. In consequence of the after the blades have been secured against rocking. If, on the other hand, it is desired to drive the ship backward at once from the middle position of the propeller-blades, the securing-apparatus is first loosened and the engine is started in any direction, after which, as soon as the propeller-blades have have been secured in proper position after having rocked with their axle h the direction of rotation of the engine can be again reversed.

What I claim, and desire to secure by Letters Patent of the United States, is

1. A propeller having blades mounted rotatably about an axis perpendicular to the shaft and unsymmetrically shaped with respect to their axis of rotation so as to automatically move under the water-pressure; in combination with mechanism by means of which the blades may be secured either in line with the longitudinal perpendicular plane of the ship or in any position assumed upon rocking the blades about their axis, substantially as described.

2. In combination with the shaft, the boss or enlargement on the end thereof, the propeller-blades having hubs or studs pivotally mounted in sockets in the boss; pins projecting through openings in the end of the boss and adapted to engage the hubs of the blades to lock them against axial rotation, springs for forcing said pins inwardly, and means for retracting the pins, substantially as described.

3. A propeller having blades rotatable about an axis perpendicular to the shaft and shaped unsymmetrically with respect to their axis, pins adapted to enter in openings in the hubs of the blades, the said pins passing through openings in the end of the bladesupport, and means for retracting the pins from the hubs, substantially as described.

In testimony whereof I have hereunto set my hand in the presence of two witnesses.

. EILT S. JACOBS.

Witnesses:

M. R. MEENTZ, TH. WEDEKAMPER. 

